[llvm] [SelectionDAG] Split sd_use_iterator into sd_user_iterator and sd_use_iterator. (PR #120531)

[Sergey Barannikov via llvm-commits]

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@@ -837,29 +835,72 @@ END_TWO_BYTE_PACK()
     }
   };
 
+  class user_iterator {
+    friend class SDNode;
+    use_iterator UI;
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s-barannikov wrote:

That's not OOP. Rather, they should both derive from one of the classes from `ADT/iterator.h`. Not sure about compile time impact though.


https://github.com/llvm/llvm-project/pull/120531